Finally I've got the QSL from T31T. Worked him on SSB on 20 m. Was not easy to get the QSO but I finally managed to get trough the pile and the QSO was there.
But I'm still missing T31 on several band slots.
By the way my IOTA score is at the moment 480 islands. I'm slowly getting there.
Enjoy the T31 QSL.